The present invention relates to a film useful for glare control, especially useful in connection with cathoderay tubes, or other monitor screens of the type presently used in connection with computers.
With the advent of computers, and especially in connection with the extensive use of computers, one of the problems that has arisen in connection with the use of computers is the amount of reflected light that emanates from the computer screen. This has become an especially troublesome problem for those persons who are obligated to use computers in connection with their daily work process, especially when such persons are in front of a computer screen for several hours per day. It has been found that the reflected light which comes from the computer screen, in addition to the glare of the image on the screen, causes eye strain and other related problems detrimental to the health of the persons utilizing the computer.
For this reason, the art has been replete with various attempted developments to either cover the computer screen, or to apply some type of a coating to the screen which would have the effect of reducing the glare especially of reflected light.
The prior art has developed such items as plastic screen overlays which were employed for overlying a monitor screen, but usually have the effect of darkening the image or picture emanating from the computer screen. Such screens were believed to reduce the eye strain on the user by softening the image or picture from the screen mainly by having the effect of cutting the brilliance of the light waves and basically darkening the screen. However, in most instances, such screen overlays were made of plastic, and in and of themselves, also reflected light. This was especially apparent in rooms which were lit with neon-fluorescent lighting, the light waves emanating from the fluorescent lighting further reflecting off the plasticized screen which was used as an overlay on the computer monitor screen.
Various attempts were then made in the prior art to develop coatings of various types which could be applied to the screen of the computer, and would have the effect of either diffracting, or reflecting light away from the eyes of the user. For example, U.S. Pat. No. 4,734,295 was directed to a glare control composition and a method of applying the same. The teaching of this patent was to provide a glare-controlling coating with a reflective, transmissive surface which consisted of a liquid dispersion comprising an organic polymeric particles and a flattening agent. The organic polymer was selected from the group of dispersion containing latices, varnishes, polyurethane dispersions, lacquers, coreactable systems or condensing systems. The flattening agent was selected from either a magnesium carbonate, cellite, alumina hydrate, wax, aluminum stearate, zinc tungate, silica, and zinc stearate. The patent teaches that a composition formed in this manner when applied to a glass or plasticized transmissive surface, created a coating which functioned at least in part to prevent reflective light from such surface. Indeed, the patent teaches the use of providing a second coating on the screen, the second coating being an inert fluid coating having the effect of controlling the degree of the anti-glare effect and enhancement of contrast.
It is clear that any such coating applied to a monitor screen must in itself be light transmissive or clear, such that the images appearing on the screen would still be visible to the user. The object of the coating would be to either deflect light away from the eyes of the user, or to absorb light such that the light would not be reflected back to the eyes of the viewer.
Various other patents illustrate still other types of compositions employed as a coating. For example, U.S. Pat. No. 4,604,297 discloses a transmission enhancing coating which consists of a polyvinyl acetate particulates and water or an acrylic resin and an aqueous dispersion of polyvinyl acetate. The patent teaches that such a coating would have the effect of preventing reflection from the glass type screen surface in order to prevent strain to the eyes of the viewer.
Still another prior art patent, namely U.S. Pat. No. 4,765,729 discloses the provision of an anti-reflection optical article which comprises a substrate consisting of a single-layer or multi-layer anti-reflection film having a surface film composed of an inorganic substance formed onto the substrate, and a coating of an organic substance containing a curing material formed on the surface of the anti-reflection film. The basic ingredient of the composition is a silicon dioxide or other silica containing materials. However, the method of the subject patent appears to require multi-layers of coating in order to operate properly as an anti-reflection multi-layer film.
Still another more recent patent which discloses an anti-reflective coating for use in connection with such substrate is U.S. Pat. No. 5,104,692. This patent teaches the use of a first bottom layer containing less than ten percent by weight of a titanium dioxide, and a titanium-free top layer which contains polysiloxane. Hence, the teaching of the subject patent requires a two-layer film composition in order to accomplish its anti-reflective characteristic. Similarly, various other patents disclose other types of coatings formed by a variety of compounds, including polyurethane resins.
The present invention is intended as an improvement with regard to such prior art patents in that the present invention only requires a single coating forming a film over the monitor screen and functions particularly well as an anti-reflective coating. The present invention further provides a coating which permits ease of removal since the coating, once dried on the monitor screen may easily be removed by a common household solvent. Hence, the user is able to prevent coating build-up so that if the coating should fail with age and time, the user may easily remove the coating, and apply a fresh anti-glare coating onto the monitor screen.